def primeset(N): #N以下の素数をsetで求める.エラトステネスの篩O(√Nlog(N))
    lsx = [1]*(N+1)
    for i in range(2,int(-(-N**0.5//1))+1):
        if lsx[i] == 1:
            for j in range(i,N//i+1):
                lsx[j*i] = 0
    setprime = set()
    for i in range(2,N+1):
        if lsx[i] == 1:
            setprime.add(i)
    return setprime

N,L = map(int,input().split())
setp = list(primeset(L))
setp.sort()
cnt = 0
for p in setp:
    if  p*(N-1) > L:
        continue
    cnt += L-p*(N-1)+1
print(cnt)